Transmission



Feb. 6, E951 M. P. wlNTHER ETAL TRANSMISSION Filed May 1'1, 1945 8 Sheets-Sheet l Feb. 6, 1951 M. P. WINTHER ETAL 2,540,639

TRANSMISSION Filed May 1l, 1945 8 Sheets-Sheet 2 y FeG. 2..

TRANSMISSION M. P. WINTHER ET AL Feb., 6, 1951 Filed May 11, 1945 xvmm.

mm mm www Mm QN mwN SN mow Feb., 6, 951 M. P. WINTHER ETAL 2,540,639

TRANSMISSION Filed May 11 1945 8 Sheets-She??l 4 Feb. 6, 1951 M. P. WINTHER ETAL 2,540,639

TRANSMISSION Filed May 11, 1945 8 Sheets-Sheet 5 Feb. 6, 1951 M. P. WINTHER ET Al. 2,540,639

TRANSMISSION Filed May 11, 1945 8 Sheets-Sheet 6 Feb. 6, 195i M. P. WINTHER ETAL TRANSMISSION 8 Sheets-Sheet '7 Filed May 11, 1945 i -Tw -JP mmm,

Emmet; QQ ok mwN Patented Feb. 6, 1951 TRANSMISSION Martin P. .Winther, Waukegan, and Anthony Winther, Kenosha, Wis., a'ssgnors to Martin I.

Winther, trustee Application May 11, 1945, Serial No. 593,236

24 Claims.

This invention\reiates to transmissions, and with regard to certain more specific features, to automatic transmissions, particuarly for automotive use but having other uses as well.

Objects Among theQseveral objects of the invention may be noted the provision of a multi-speed automatic transmission which can readily be designed substantially to duplicate any practical torque ranges required and which lends itself to practical inclusion with any ordinary overdrive arrangement; the provision of a transmission of the class described in which torque changes occur smoothly and without intervening parasitic drag action and without periods of lost torque; the provision of a transmission of the class described Which when connected provides a substantially positive driving coupling; the provision of a transmission of the class described which is of simple and compact formbut does not sacriilce generous clutch sizes where such are used; and the provision of va transmission of this class which is economical to build and easy to maintain. YOther objects will be in part obvious and in part pointed out hereinafter.

`The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will he exemp`ied in the structures hereinafter described, and the scope of the application of which will be indicated in the following claims.

Drawings In the accompanying drawings, in which is illustrated one of various possible embodiments of the invention,

Fig. 1 is a longitudinal section of the mechanical elements of an entire transmission embodying the invention;

Fig. 2 is an enlarged longitudinal section of a clutch section C of Fig. 1;

Fig. 3 is an enlarged longitudinal section of a gear section G of Fig. 1;

Fig. 4 is a cross section taken on line 4 4 of Fig. 3;

Fig. 5 is a, vertical section taken on line 5 5 of Fig. 3;

Fig. 6 is a vertical section taken on line 6 6 of Fig. 3;

Fig. 7 is a vertical section taken on line 1 1 of Fig. 2; l

Fig. 8 is a horizontal section taken on line 9 8 of Fig. 2;

(Cl. 'i4-472) 2 Fig. 9 is a vertical section taken on line 9 9 of Fig.2;

Fig. 10 is a vertical section taken on line Ill-I Il of Fig.' 2;

Fig. 11 is a vertical detail section taken on line II-II of Fig.2;

Fig. 12 is a vertical detail section taken on line I2` I2 of Fig.2;

Fig. 13 is a vertical section taken on line |3 I3 of Fig.2;

Fig. 14 is a diagrammatic view of certain electrical and mechanical controls;

Fig. 15 is a chart of operations of the elements which are most signicant to the description; and,

Fig. 16 is a schematic drawing of essential parts of a compound epicyc'ic or planetary gear train viewed substantially from line 5 5 of Fig. 3, in which only the pitch circles of a basic set of gears are shown, instead of their teeth.

Similar reference characters indicate corresponding parts throughout the several views of the drawings.

Description of electro-mechanical means Hereinafter all references to clockwise and counterclockwise rotations assume that Figs. l, 2, 3 and 16 are being viewed from the left, which is the engine or front side of the transmission.

In Figs. 5 and 6 are shown all of certain panetary or epcyclic gears 'Il and BI, butin schematic Fig. 16 only one basic set of each of these is shown, since the remainder are multiplied only for reasons of balance and strength.

Referring iirst more particularly to Fig. 1, the casing of the transmission is indicated in three sections I, 3 and 5. The bottom of section I is enclosed by an attached pan 1. The casing section I attaches to the rear of the crankcase of an automotive engine or like prime mover. The rear end of the crankshaft of said engine includes the usual flange 9 to which is bolted a flywheel II (see bots 2). This member II carries the usual ring gear I3 adapted to he engaged by an engaging and disengaeing starting pinion, but since the starterA construction forms no part of the invention it will not further be described.

Piloted for rotation in a center sleeve bearing I5 of the flywheel II is in the left end of a lowspeed shaft I9. Splined near the end of shaft I9 is the inner race I6 of an overrunning clutch I'I. This clutch is detailed in Fig. 13. It allows the flywheel I I to overrun the shaft I9 clockwise but does not allow the shaft to overrun the ilywheel clockwise. Thus the engine maybe cranked from shaft I9 if necessary, as well as from the starter gear I3.

On its right-hand end the Shaft I9 is piloted in a sleeve bearing 2|, the latter being located in a counterbore 23 of a driving quill 25. This quill 25 at its right-hand end is, by-means of a ball bearing 21, supported within the section of the casing. Outside of this bearing this quill has keyed to it a coupling flange 29 for fastening it to the drive shaft assembly (not shown) of the vehicle on which the transmission is located. A packing gland 3| functions as a grease retainer and means for excluding foreign material from the outside. .The left-hand end of the quill is supported within a sleeve bearing 33, the latter being supported in a rotary gear cage member 35, made in two parts 31 and 39 bolted together as shown at 4I. This outer cage has a sleeve 43 at its rear end which is supported upon a ball bearing 45 in the case section 3. It also has a sleeve 41 at its left end. supported in a ball bearingr 49. This bearing 49 is located upon an annular support 5| bolted at 53 to the inside of case section 3. Attached within thecage is an internal gear 13.

On the right-hand end of lthe sleeve 43 of the outer cage 35 is a one-way bra-ke indicated genericallv bv the numeral 55 (Fie. 4) This brake is constituted by an outer stationary race 51 in the section 3 and an inner race 59 solined to 43 and having wedge-shaped's'ections 6| in which are brake rollers 63. The arrangement is such that, viewed from the left, the outer cage 35 may rotate clockwise but never counterclockwise. A gear shown at numeral 95 is for an auxiliary takeoif drive for operating certain centrifugal governor switches 305, 331 and 349, to be mentioned below.

The ouill 25, which it will be recalled is rotary in the bearing 33 within the outer cage 35, is provided at its left end with a three-armed planetary support 61 from which extends supporting gudgeons G9 for a set of planetary gears 1| The gears 1I are rotary on the gudgeons 69. Exteriorly they mesh with an annular gear 13 which is attached to the interior of the outer cage 35. Interiorly the planetary gears 1| mesh with a central sun gear 15, the latter being carried on the right-hand end of the shaft I9. Shaft i9 hereafter will be called the low-Speed shaft.

The pins 99 also support an annular, bellshaped member 11, pin fastenings 'I8 being em ployed for the purpose. This member 11 with the arms 61 may be called an inner planetary cage, tthe members 61 and 11 rotating together as a uni The bell member 11 carries an annular gear 19 which meshes with a set of planetary gears 8| rotary on gudgeon pins 83 extending from the part 39 of the rotary outer cage 35. The gears 8| mesh with a central sun gear 85 which is formed on the end of a drive tube 81. Tube 81 will hereafter be called the second-speed tube. At its central portion this tube 81 is keyed to the central hub 89 of an electric brake drum 9|, later to be described. This central hub 89 is supported in a ball bearing 93. The support for the outer race of the ball bearing 93 is in a fixed member 209, other functions of which will later be described. The extreme left end of the tube 81 is splined at 94 with a hub 95 with enough looseness of t to allow for slight axial movement of the hub 95 without relative rotary movement. The hub 95 has a rotary bearing relative to the shaft I9 through a sliding ball bearing 91. Attached to the outside of the hub 95 is a clutch plate 99 which peripherally carries friction facings |0I.

A second hub |03 carries a clutch plate |05. Hub |03 is splined to the shaft I9 at |01 for axial movement without relative rotary movement. This second clutch plate has friction facings |09.

Both clutch plates 99 and |05 are housed within a ring bolted to the flywheel II as indicated at |I3. This ring III includes an integral ring |23. Splined to the left end and on the interior of the ring I I I is an axially movable pressure plate II5. The splines show at ||2 (see Fig. 11) Although axially movable, this plate ||5 is rotan7 with the ring III. Splined at the right within ring is a second pressure plate |25. The splines for this show at |26 (see Figs. 10 and 12).

From the .pressure plate I|5 extends a group of (three) pins I I1 which pass through holes ||9 in |23 and slots |2| in |25 and |33. A group of compression springs |21 traversing suitable passages |29 in the ring |23 serve to bias apart the pressure plates I |5 and |25, away from the clutch plates |05, 99.

The ring |25 may be pushed so as to force clutch plate 99 against |23 by action of several (three) levers |30 pivoted at clevises |3I which are bolted to a housing member |33 fastened to the ring and rotary therewith (see Fig. 10). Anvil means |35 on the ring |25 receives pressure from the levers |29 through cams |31 on the levers.

The clutch levers |30 are angularly controlled from pins |39 which extend through openings |4| in the housing |33. These pins |39 are supported upon a ring |43 which is carried on the outer race of a ball bearing |45. Thus the levers |30, control pins |39 andlring |43 are all rotary, but, as will be seen, the control pins |39 may be moved axially for operating the levers. Thus when the levers |30 are moved clockwise (Fig. 1), they press the ring |25 toward the stationary ring |23, and under pressure grip the clutch disc 99.

A second set of levers |41 is used for axially moving the pins II1, and hence the ring ||5 (see Fig. `10). This is accomplished by pivoting the levers |41 at |49 on suitable extensions |5| from the cover |33. The levers |41 are notched as shown at |53 for cooperation with a knifeedge bearing |55 of adjustable heads |51 on the pins ||1 (see Fig. 2). Thus when the levers |41 are rotated clockwise (Fig. l), they move the pins to the right (Fig. 1), thus drawing over the ring I5 into which they are threaded. Since the clutch disc |05 is between rings ||5 and |23, it may thus be clutched or released.

Movement of the levers 41 is accomplished by contacting their ends |59 with a flange ISI forming part of a control tube |63. This tube at its other (right) end is attached to a bell which in turn is attached to the outer race of a ball bearing |61.

From the above it will be clear that the clutch plates 99 and |05 are clutched or declutched from the axial movements of the ball bearings |45 and |61 `respectively. Thus when the ball bearing |45 is moved to the left, there is a closing in on the clutch disc 99 which drives the second-speed tube 81. When the ball bearing |45 moves to the right this clutch disc 99 is released. When the other ball bearing |61 moves to the right, there is a closing in on the clutch plate |05 which drives the low-speed shaft I9. When bearing |61 moves to the left this clutch plate |05 is released.

For brevity hereinafter, the clutch parts which are operated by the levers |41 will be referred to as clutch A (for shaft |9 and those operated by the levers |30 will be referred to as clutch B (for tube 81). Y

Control of the axial movement of the ball bearings |45 and |61 is obtained as follows: The inner race of the bearing |45 is affixed to a control sleeve |69 and the inner race of the bearing |61 is aixed to a control sleeve |1|. These sleeves |69 and |1| are positioned around a sleeve y |13 having. a central stop |15. This sleeve |13 is attached to an extension sleeve |11 extending from the housing part |33. The sleeve |63 above described in connection with bell |65 is rotary between the sleeve |11 and the drive tube 81. The extension sleeve |11 and the attached co'ntrol sleeve |13 are always rotary with the clutch housing, that is to say, with the driving parts of the clutches A and B.

The outside of the sleeve |13 is helically threaded with semi-circular grooves |14`and |18. Likewise, the insides of the control sleeves |69 and |1| are threaded as at |16 and |80. The pitches of the threads |14 and |16 are equal and right-handed: those of |18 and |80 equal and left-handed. The semi-circular grooves thus produce complementary helical channels into which intertting ball bearings |19 are located. In other words, the sleeve |13 and the control sleeves |69 and |1|, respectively. are connected by anti-friction ball-bearing thread means, sometimes referred to generically as an Edison screw.

Thus if, while the control sleeve |13 rotates clockwise, either control sleeve |69 or |1| is retarded, the resulting relative angular movement will cause a threading action of either sleeve |69 or 1| away from the stop |15. The resulting axial movement of the control sleeve |69 controls the levers |30 through bearing |45 to close clutch B; and the resulting axial movement of the sleeve I1| through bell |65 and sleeve |63 controls the levers |41 to close clutch- A. If the rotations of control sleeves |69 and |1| are not retarded, these will tend to rotate with the sleeve |13. The helical threads are frictionless enough, and of enough pitch that under these conditions the clutch opening pressure from springs |21 Will, through the levers |29 and |41 and appurtenant parts, drive the control lsleeves |69 and |1| back against the'central stop |15.

Contolled retardation of the control sleeves |69 and is obtained electrically as follows: Sleeve |69 has attached thereto a magnetic eddycurrent conductive ring |8|. Sleeve |1| likewise has attached thereto a magnetic eddy-current conductive ring |83. Electric brake control means for the ring |8| is provided by a peripheral electromagnetic coil |85 which is within the connes of a two-piece magnetic housing` |81 having alternating pole-forming teeth |89 and |9| which extend Within the coil. These teeth |89 and |9| overlap axially and are spaced peripherally. Being in a toric flux eld circuit of the coil |85 (see the dash lines |93; Fig. 2), these teeth become alternately north and south. The flux eld passing between alternate teeth also passes through the magnetic material of the ring |8|. Thus rotation of the ring is resisted in proportion to the energization of the coil |85, this being due to the magnetic reaction from the engendered eddy currents. When rotation is resisted, the ring threads out from the stop |15. 'Ihe closing action of clutch B is therefore under control of current in the coil |85. With light current the clutch closure force is light; and with heavy current the closing force is stronger.

Likewise, the ring |83 has surrounding it an electromagnetic coil |95 located in a two-part circular magnetic member |91 having alternating polar teeth |99 and 20|, which reach under the coil |95 and in that region overlap axially and are spaced peripherally. As above described in connection with coil 85, the toric flux field from coil |95 forms alternate north and south poles in the teeth |99, 26|, the flux circuit closing through the ring |83 and inducing a magnetic drag according to the energizaton of the coil |95. In the case of both rings 8| and |83 the drag action is caused by the 'reactive flux from induced eddy currents by relative motions of the rings with respect to their respective elds.

The assembly of coil and ring |61, and also the assembly of coil and ring |91 are attached to a stationary support 263 extending from an interior wall part 205 of the housing part `Attached to the other side of the Wall 295 and located Within the rotary brake drum 9| is a stationary assembly indicated generally at numeral 201. This assembly is constituted by a central stationary magnetic ring 209, within which is said bearing 93. It will be remembered that the brake drum 9| is rotary in said bearing 93 with the tube 81. The ring 239 has bolted to opposite sides magnetic rings 2|| and 2|3. 'The bolts 2|5 which hold the ring 2| also support the ring 289 with respect to the Wall 285. The bolts 2I1 hold the ring 2 |3'to the ring 299. This assembly provides annular spaces 2 I8 and 229 for annular electromagnetic coils 2|9 and 22| respectively. rEhe ring 289 is provided with central, radially extending, peripherally spaced polar teeth 223. These havev opposite extensions 225 and 226 over the coils 2|9 and A22| respectively. The ring 2|| also has peripherally spaced polar teeth 221 having axial extensions 229 which alternate with the extensions 225 (Figs. 'I and 8). r,These extensions 225 and 229 thus alternate peripherally. Likewise, the ring 2|3 has polar teeth 23| with extensions 235 ever the coil 22|. The extensions 235 axially lap the extensions 226 and alternate with them peripherally. The coils 2|9 and 22| are so wound that the toric ux fields therefrom dash lines 2|6 in Fig. 2l make all of the teeth 223 (including extensions 225 and 226) of one polarity and the teeth 221 and 23| of another f polarity so that around the outside of each coil vare alternating north and south magnetic poles.

The ux flowing out of the north poles traverses the magnetic drum Sl and then leaves this drum and enters acjacent soz-.th poles. Therefore under conditions of relative rotation between the brake drum 9| and the field member 289, eddy currents are engendered in the drum which produce a reactive field effecting a retarding action. rThe retardation increases with increased current carried by the coils 2|9 and 22|.

Around the brake drum 9| is located a friction brake band 233 which is anchored to the stationary member 3 at the anchor 266 'see Fig. '1) The other end 231 of this brake band is Controlled from a lever 239 pivoted at 238 to the case 3. The lever 239 has connected thereto a control rod 24'| which reaches to suitable manual brake-setting means.

Around .the rotary outer cage 35 are formed teeth 243 for engagement by a dog 245 of a plunger 241. A spring 248 normally biases the plunger so as to disengage the dog 245. On the top of this plunger is an extension 249 operable by means of a translation cam 25| for forcing the plunger into a position wherein the dog 245 will interlock with the teeth 24'3. A rod 253 of which the cam 25| forms a part is connected through a suitable mechanical linkage 252 with a manual control lever 292 (Fig. 14).

Electro-mechanical operation The electro-mechanical operation of the device, exclusive of circuit controls, is as follows, in which schematic Fig. 16 should be followed with the other pertinent figures, particularly 1, 2 and 3:

In neutral or disconnected position, the clutches A and B are open. -Coils |85, |95, 2|9 and 22| are deenergized. Under these conditions the flywheel I|, ring III, clutch cover |33, extension sleeve |11, sleeve |13, control sleeves |69, |1I (against stop T15i,rings ISI, and |83 all rotate. With these parts rotate the driving parts of the clutch, including rings H5, |23, |25, the levers |30, |41 and associated parts. But the clutch plates 99 and |05 do not rotate because the clutches are open. Hence neither the shaft I9 nor the sleeve 81 is driven. The clutch control rings |8| and |83 rotate freely with the clutch case because there is no electromagnetic braking action from the deenergized eld coils |85 and |95.

Under the above conditions springs |21 move the levers and |41 so as to bring the sleeves |69 and |1| against the stop |15. It will be remembered thatthe pitch on the threads on members |13, |69 and |1I is enough that the force on the levers from the springs |21 will permit thread.- ing down of said sleeves |69 and |1| to the stop |15. The portions of the threads |14 under control sleeve |69 are right-handed; those under the control sleeve |1| are left-handed, it will be recalled.

For 10W-speed operation (highest torque), clutch A is closed by energizing the coil |95. Clutch B is open, coil |85 deenergized. Such energization of coil |95 causes a flux circuit through the lapped portions of the teeth |99, 20| and through the ring |83, resisting the free angular motion of the latter. This causes axial lefthand threading of the sleeve |1I to the endwise position shown, which through bell |65 and tube |63 and ange |6| rotates the levers |41 clockwise. Thus through the fulcrums |55 and the bolts ||1 the ring |I5 is moved toward the ring |23, thus gradually frictionally gripping the clutch plate |05 so that the latter gradually picks up speed. Finally the clutch locks fully engaged and the mechanical drive is then from clutch plate A, low-speed shaft |9 (Fig. 16), sun gear 15, planetary gears 1|, which gears 1I, since the quill 25 is initially stationary, tend to drive the internal gear 13 counterclockwise with respect to the rotation of the shaft I9. Gear 13 being a part of the outer cage tends to drive the latter backwards but such backward rotation is resisted by the one-way brake 55. Therefore the planetary gears 1I react on gear 13 as a fixed fulcrum and drive the planetary arm member 81 which in turn drives the quill 25 at reduced angular velocity and correspondingly increased torque. An exemplary speed ratio of shaft I9 to quill 25 might be 3:1 corresponding to a torque ratio of 1:3. It will be noted that under these conditions the member 11 rotates along with the annular gear 19. That is, what has been identified as the inner cage 81, 11 rotates. This drives the gears 8|, 85, tube 81, brake drum 9|, and the clutch plate 99. Since, however, the clutch B is at this time open and coils 2|9, 22| are deenergized, this constitutes a mere parasitic rotation without any Substantial parasitic drag. Gears 19, 8| and 85 operate as a simple train, all their axes being fixed under the stated conditions.

It is emphasized that with the tube 81 rotates the brake drum 9|. For second or intermediatespeed operation, the coils 2|9, 22| are next energized, the venergization of coil |95 being unchanged, whereupon the ux field circuits from the teeth ends 225, 229; 226, 235 engender eddy currents in the drum 9|, thus slowing it. This amounts to an electric clutch action, Thus gears 8|, instead of freely driving the gear 85 with sleeve 81, now act against gear as a resisting fulcrum. The reaction point for the system is then transferred from the one-way brake 55 to the electric brake drum 9|. This will best be understood by considering a limiting condition in which the brake drum 9| is stationary, although this limiting condition in fact doesA not quite occur. In fact, the brake drum 9| is slowed considerably but not stopped, since some relative motion is required between it and the stationary fields from the windings 2| 9 and 22| in order to generate the necessary eddy currents for providing the flux interaction which provides the necessary reacting torque. But Whether drum 9| stops entirely or only approaches that condition is a matter which does not affect the principle. This principle is that the gear 85 then becomes a xed, or more nearly xed fulcrum.

Thus when the change is made from low speed to second or intermediate speed, the braking of the drum 9| causes the former idling action (in low speed) of the inner cage 11, 61, through the gear train 19, 8|, 85, to the drum 9|, to be blocked, and converted into an epicyclic action of this train. Gear 85 is then more or less blocked, being connected with the drum 9|. 'Ihe gear 85 then becomes amore nearly fixed fulcrum. Thus (Fig. 16) rolling action of planetary gears 1| within 13 pulls along cage 61, 11 and internal gear 19. I'his rolls planetary gears 8| around partially blocked gear 85, thus revolving pins 83 and rotating forward member 39 and the outer cage 35. Thus this epicyclic action advances the outer cage 35 so that the ring gear 13 (which in low gear was a'stationary fulcrum for gear 1|) in second speed becomes an additional advancing fulcrum. As a result the roller brake 55 releases, since it resists only backward movement of the sleeve 43 connected to the outer cage 35 and does not resist forward movement thereof. Thus the effect of the resisting fulcrum at gear 85, and the advancing fulcrum at gear 13 increases the speed of the quill 25 and inversely decreases the torque. An exemplary speed ratio in second speed of shaft 9 to quill 25 might be 3:2 corresponding to a torque ratio of 2:3. Thus second or intermediate speed is obtained. The exact ratio at any instant depends upon the rate at which drum 9| is allowed to move by the electric brake constituted by the ux from coils 2I9, 22|.

For high-speed operation the clutch B is closed by energizing the coil |85 while coils 2|9 and 22| are deenergized, thus again freeing the brake drum 9I'for idling action. With both clutches A and B thus closed, the shaft I9 and the sleeve 81 operate at the same speed with the result that the gears 85 and 15 are relatively locked. The result is that both the inner cage 11, 61 and the outer cage 35 are relatively locked and rotate together as a group, and the quill is therefore driven at the angular velocity of the flywheel In other words, this is a straight-through drive at 1:1 speed and torque ratio, without change through the transmission.

For reverse rotation of the quill 25 relatively to the rotation of the flywheel the dog 245, by operating lever 232 to reverse position R (Fig. 14) is brought into interlocking relationship with the teeth 243, thus locking the outer cage which makes roller brake 55 functionless. At this time clutch B remains closed, coil |85 being energized but at this time coil |95 is deenergized thus allowing opening of the clutch A. At this time the coils 2I9 and 22| are in deenergized condition. The result is that only the sleeve 81 is driven from the flywheel At this time there is no resistance at the electric brake drum 9|. Clockwise rotation of the gear 85 drives the gears 8| counterclockwise, thus driving the gear 19 counter-clockwise, along with the inner cage 11, 61 which drives the quill 25 backward according to the gear ratio determined by gears 85, 8| 19, which act as a simple non-epicyclic train. They act as a simple train because the outer cage 35 is at this time locked by the dog 245. At this time the gears 1| are rolling epicyclically within the then xed gear 13 and driving the gear 15 counterclockwise. This drives the shaft |9 counterclockwise along with the plate of clutch A, but since clutch A is open this is a mere idling action of these parts without parasitic drag.

The velocity ratio in reverse is of the order of that in low speed (about 3:1) and is determined by the ratio of the pitch radii of gears 85, 8| and 19. The torque ratio in reverse is of course the inverse of the velocity ratio (about 1:3).

The purpose of the overrunning clutch |1 is to allow' for cranking the engine from the quill Z5, for example when the battery is dead in an automobile in which the transmission is located. Thus the automobile may be pushed on the road to crank the engine. Since the car is usually pushed forward under such conditions and low gear connection is not wanted because of its unfavorable reverse torque, the manually-operated brake band 233 is provided. This locks the drum 9| by a manual setting. The outer cage 35 is at this time not locked at 243. Clutch A is open, but clutch |1 takes its place. Clutch B is open. The gears then operate as follows (Fig. 16)

Cage 61,-11 moves clockwise, rolling gears 1| within gear 13. Since the motion ofA gear 15 is at this time resisted, gear 13 tends to be driven clockwise which carries along 11, 19, thus rolling gears 8| on locked gear 85. This causes gears 8| to advance pins 83 clockwise, carrying along cage 35, which provides a moving fulcrum for gears 1|, with the result that they drive gears 15 clockwise. The gear ratio is approximately equal to that of second-speed operation, the only difference being that due to a slipping braked condition of 85 (in second), as compared to a completely braked condition of it (in cranking).

The gear section of the device is provided with a suitable charge of lubricant which is kept in circulation by the operation of the gears. The lubricant is guided into the proper channels by channeling members such as 255, 251, 259 and centrifugally-operative circular channel members 26|, 263 and 265. The details of these items and their cooperation are not discussed herein.

They do not form part of the invention per se.

Electric controls In Fig. 14 is shown an electric circuit for control purposes. Before describing this it should be observed that it is intended that the clutch A for low-speed operation is to be engaged simply by speeding up the engine, in order to give the same effect as if the car were started by means of a centrifugally-operated clutch responding to engine speed. Experience has shown us that very smooth starting action can be obtained when using a centrifugal clutch control in low speed. However, centrifugal clutches do not operate satisfactorily for second and high-speed operations. Many times a car is called upon to operate under full engine torque in second and high speeds. If for example a hill is slightly steeper than it should be for the gear ratio involved in second or high, the car will slow down until the clutch begins to slip but a centrifugal clutch, if used, will not permit the engine to stall. Therefore the clutch continues to slip until the friction surfaces burn out. Such a condition is seldom, if ever, encountered in low gear.' Therefore, a centrifugal clutch is satisfactory for low gear but is not proper for second or high gear.

The present transmission obtains the equivalent of the smooth action of a centrifugallyoperated ciutch in low gear, but it is actuated by means of an electric relay system.

It is also important preliminarily to observe that intermediate or second speed should be permitted to take eiect at other than a fixed road speed, that is, the governor used should only prepare for second-speed operation pending fulllment of other desirable conditions. For example, when accelerating rapidly, the point at which second speed should come into operation is to be automatically determined by manifold pressure drop. Thus the point at which intermediate speed comes into operation is to be controlled by such pressure drop (vacuum increase) and the car speed at which the second gear connection is made depends upon the rate of acceleration and the throttle position. The greater the throttle opening, the higher the car speed will be before second speed engages. Once second speed is engaged, it should lock in. This is done by means of a contact in an electrical control circuit.

The statements above made in the reference to the engagement of intermediate speed also apply to a certain extent to the engagement of high speed. Arrangement is also made so that when the throttle control (gas pedal) is fully depressed high speed cannot engage at all. However, by a slight release of the gas pedal it (high speed) is engaged, provided the manifold vacuum in the engine is high enough. Otherwise the engaging of high speed is similar to that of second and is covered by similar operating factors.

Provision is also made so that once high-speed operation is brought about, it will continue until the car speed drops to 8 M. P. H. or less, unless the gas pedal (throttle) is opened sufficiently for a quick pickup. Lower-speed operation will occur automatically under the latter conditions if the gas pedal is depressed far enough. In addition, a selection occurs at this time of low or second speed depending upon the car speed. Low speed will take effect below 8 M. P. H. and second speed above 8 M. P. H. The effect depends upon a governor switch responsive to propeller shaft operation.

11 Reference to Fig 14 will make the above matters clear. driven from the engine, that is, its speed is proportional to engine speed. A cross bar 269 attached to the shaft 261 has pivots 21| for centrifugally-operated weights 213. The right-hand ends of the weights tend to ily outward with increased speed and the left-hand ends press againstsprings 215. Each weight includes a lug 211 which, as the weights move outward, axially moves a sleeve 219. Attached to the sleeve 219 is the conducting pressure plate 28| of a carbon pile 283. Theother conducting stationary plate of the pile is s hown at 285. As the speed increases the resistance of the pile decreases.

'Ihe car battery is shown at 281 and the engineignition switch at 289, these supplying point 286 in the circuit shown.k

The carbon pile 283 is in the circuit 281, 289, wires 29|, 293, point 288, wires 295, switch 291, wires 299, control coil |95`-of clutch A and wire 30| to ground, thus closing a circuit. This is shown by solid arrows. As the pedal 303 is manipulated to open the engine throttle, and so long as switch 291 is closed, the coil |95 is increasingly energized with acceleration of the engine and car. As the engine speed increases, the centrifugal governor reduces the resistance in the carbon pile 283 and thus clutch A is smoothly closed.

The switch 291 is one of a set of manually set switches 291, 329, and 351, all operated from a single control bar 290. This bar is controlled from a manually-operated lever 292 which has a forward position F shown in which switches 35|, 291, 329 are shut when switch 361 is open. This lever 292 also has a reverse position R in which, when switch 351 is closed, switches 35|, 291 and 329 are open. It also has a neutral position N in which all of these switches are open.

At 305 is shown one of a set of governor switches (395, 331 and 339) which are responsive to car speed, being driven from the takeoll drive associated with gear 65. The details of the governor mechanisms are unnecessary, since such are well-known, being operated by centrifugal means, similar to that shown in connection with the carbon pile 283.

The switch 305 closes at 12 M. P. H. and reopens at 8 M. P. H. Switch 331 closes at 20 M. P. H. and opens at 8 M. P. H. Switch 339 closes at 20 M. P. H. and opens at 8 M. P. H. These switches all prepare their respective circuits for operation at the proper speeds.

A vacuum-controlled switch 301 has an operating stem 309 extending to a head 3|| which is normally held up a rocker 3|2 and spring 3|4. 'I'he stem 309 carries an operating element of a switch 3|6. Switch 3| 6 closes with switch 301. A plunger 3|3 is operated from a rocker 3|5 pivoting at 3|1. A spring 3| 9 normally biases the rocker clockwise to lift the plunger 3| 3. A vacuum bellows 32| connected by a line 323 to the engine intake manifold causes counterclockwise movement of the rocker 3|5 according to pressure drop in the manifold, thus tending to close switches 301 and 3|6.

Switches 321 and 312 are magnetic contactor switches.

Second or intermediate speed maynormally be brought about at about the time.. when the car reaches 12 M. P. H. under low-speed conditions. Then the governor switch 305 closes and the following circuit (shown by dotted arrows) is energized: point 286, wire 325, closed switch In this figure auxiliary shaft 261 is 321 (biased shut by spring 328), switch 329, wires 33| including the closed governor switch 305 and switch 301 (which will be closed, provided the manifold pressure has been reduced enough), wire 333, coils 2|9, 22| and wires 335, 30| to ground. It will be recalled that mechanically in order to go into intermediate speed from low speed it is not necessary to deenergize the coil |95 or open the clutch A, but rather thatclutch A shall remain shut. Normally at 12 M. P. H. in low speed, the vacuum in 32| is enough to hold switch 301 shut but if the operator has the throttle open Wider than normal, thus tending to break the vacuum, second-speed operation may be delayed, pending closure of switch 301 which awaits vacuum increase (pressure decrease) with increase of engine speed at the given throttle position. The magnetic contactor switch 312, which is connected across switch 301 by wires 362 and has a. holding coil 368 connected across coils 2|9 and 22| by wires 389, serves to hold this circuit even though switch 391 should reopen. This prevents the nuisance of having the speed drop back to low from second, once the latter has been engaged, even when the throttle is opened so wide that resulting increase in manifold'pressure in 32| would cause reopening of switch 301. A spring 310 is used to bias switch 312 toward open position.

As the engine speeds up in second gear, the vacuum will increase (pressure decrease) in the bellows 32|. High speed will then normally be inaugurated at 20 M. P. H. at which speed governor switches 331 and 339 close. Current then flows through the following circuit (shown by dashed arrows) Wire 34| which includes switch 331, part of wire 295, wire 343, a normally closed throttle switch 346 (the function of which will be given below), wire 345, time-delay reactor 341 (the function of which will be given below) wire 349, switch 35|, switch 339, switch 3|6 (at this time normally closed by sufficient vacuum in bellows 32|), holding coil 355, wire 351, control coil |85 of clutch B, and wire 359 to ground. Once the switch 3|S is closed, it is held closed by the holding coil 355 The coil 350 of the magnetic contactor switch 321 islconnected across coil (see wires 362) and at this time opens the dotted arrow circuit through coil 2 |9, 22|.

The purpose of the reactor coil 341 is to provide a slight time delay for high-speed action while the switch 321 in the second-speed circuit is being drawn open.

Reverse connection is accomplished when the manually-operated shifting lever 292 is set to reverse position R, which opens the switches 291, 329 and 35| while closing switch 361 in a wire 389. This obviously directly re-energizes the coil |85 without current passing through 341, 35|, 339, and 3|6, which closes clutch B. In this case switch 331 is open and wire 389 therefore receives its current from point 285 via the carbon pile 283 and point 288. Thus the control of car acceleration in reverse gear by carbon pile 283 is similar to the control in low gear. Switch 321 is held open by energization of the magnetic contactor coil 350. The lever 292 is linked with member 253 and when lever 292 is in reverse position R the dog 245 engages teeth 243. This supplies the proper mechanical conditions for reversing the gear train, as above made clear.

The pedal-operated throttle switch 346 is in the high-speed (dashed-arrow) circuit, condenser 311 being connected across it for reducing arcing. This switch 346 is adapted to be opened by 13 a tab 319 on the accelerator pedal 303. Opening `xzccurs after the pedal has reached the dottedline position shown, against a spring 38|. When the pedal 303 engages the spring 38| the operator is warned that the switch 346 will open with A slight release on the pedal 303 away from the spring will close switch 346, and then if the manifold vacuum is proper switch 3I6 will close and energize high speed.

It should also be noted that either low or second speed will become effective automatically upon depressing the pedal 303 for quick pickup, if spring 38| is depressed sufficiently to permit lever 319 to open contact 346. Whether low speed or second speed engages depends on the car speed. Low speed will be engaged below 8 M. P. H. due to the.propeller-shaft-responsive governor switch 305 opening below 8 M. P. H which prevents the coils` 2|9, 22| of brake 9| from being energized. Under such conditions only the coil |95 of clutch A will be energized which provides the mechanical conditions for low speed. Above 8 M. P. H., assuming switch 305 to have been previously closed, second speed will be engaged, due to the closed condition of the switch 305.

The magnetic contactor switch 312 is to prevent the switch 301 from deenergizing the second-speed (dotted-arrow) circuit until high speed is energized at which time the magnetic contactor switch 321 opens the second-speed circuit. The switch 312 when energized, and shunting switch 301, prevent the opening and closing of switch 301 by bellows 32| from affecting the operation of the car. Thus the effect of the vacuum bellows 32| is limited to delaying institution of second-speed operation (after low-speed operation) not only until 12 M. P. H. car speed has been reached, but also until a suicient manifold vacuum has beenobtained in bellows 32|, under the existing throttle conditions, to provide engine torque 4enough to operate in second speed. In other words, in changing from low speed to second speed the speed-responsive means is overridden when necessary by the vacuum-responsive means to provide adelayed shift.

Conclusion Fig. 15 is a chart of operations of the most signicant elements in the above description. The chart shows the conditions of the various significant structural elements in terms of the various speeds of the quill (including neutral).

Reference has been made above to the fact that the engine can be started by pushing the car even though the battery be dead. It will be appreciated that once an engine is thus started, the generator charge into the battery will usually be suicient to supply the needs'of the electrical control circuit so that the latter will from then on control the transmission. Thus 14 the car may be brought under its own power into a point where the battery may be repaired or replaced. As above made clear, starting by pushing requires the setting of the brake band--A 233 which is done from any suitable auxiliary lever or pedal.

It is believed that most of the advantages of the invention will be clear from the above but in addition it should be noted that former automatic transmissions incorporating planetary gears and depending upon mechanical means of locking the gear trains in and out were sub jected to considerable parasitic drag due to overlapping activities of brake and clutch means. It was always diflcult to adjust these so that the overlap would be a minimum and it was impractical to do without it. This parasitic drag is avoided in the present transmission because the transfer from one speed to another is accomplished instantaneously 'my electrical means without overlap and without delay in applying torque. For instance, transfer from second speed to high speed, or vice versa, is made with a high degree -at the instant that the latter close.

of precision by coordination of switches such as 321, 331 and 339, the former opening almost Therefore no parasitic drag occurs, nor is there any undue speed loss in changing speeds in the case of the present transmission.

It will be appreciated by those skilled in the art that although we show helical gears in the compound epicyclic gear train used, straight spur gears may be used, and that the same principles may be carried out in the train by means of bevel gears or other equivalent gears for the purpose.

The ter-ir cage as used herein for members 11, 61 and 31 is not to be taken as limited to the particular physical embodiments of these members as shown. The term is used in the sense that these members support gears 19 and 13 which are mounted concentrically with the quill 25, It will be observed that these cages also perform functions of epicyclic arms inasmuch as they respectively support the pins 83 and 69 for the planetary gears 8| and 1|.

In the following claims the terms compound epicyclic gear means, and compound planetary gear means, have reference to the fact that the driving member drives the gear train from tworsources (the shaft I9 and shaft 81) and that the two sun and planetV gear systemsl in the gear train react upon one another in various ways under various conditions of clutch and brake energizations to produce the various operatingspeeds and torques. Broadly speaking, this construction accounts for the fact that the present transmission involves so few parts, those that are employed being quite easy to manufacture at low cost. l

Another point of moment is the high production of resisting torque that may be obtained by the overlapping toothed constructions of the magnetic circuit members |81, |91, 2| I, 209 and 2|3. The reason for the high torque-producing efciency of such overlapped toothed constructions is disclosed in the United States Patent 2,367,636 of Martin P. Winther, dated January 16, 1945. Such eihciency is desirable in order to obtain sharply dened control, characteristics.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

We claim:

l. In a transmission for use between a prime mover and a driven member, a iirst sun gear on a first driver, a planetary gear meshing therewith, a rotary driven arm attached to the driven member and carrying said planetary gear, a first ring gear meshing with said planetary gear, a one-way-locking brake associated with said ring gear, a second sun gear on a second driver, a second planetary gear meshing with said second sun gear, a second ring gear meshing with said second planetary gear, said second ring gear being attached to said driven arm and under control of the rst planetary gear, supporting means for the second planetary gear on the first ring gear, independently operable clutches for driving said sun gears independently or together, a brake for said second sun gear, means responsive to speed of the prime mover for first closing in the clutch of the first sun gear, means responsive to the speed of the driven member for applying said last-named brake without opening the last-named clutch, and means responsive to a higher speed of the driven member for releasing said last-named brake and closing the clutch of the second sun gear without opening the clutch of the first sun gear.

2. In a transmission for use between a prime mover and a driven member, a first sun gear on a first driver, a planetary gear meshing therewith, a rotary driven arm attached to the driven member and carrying said planetary gear, a rst ring gear meshing with said planetary gear, a one-way-locking brake associated with said ring gear, a selective lock for the ring gear, a second sun gear on a second driver, 'a second planetary gear meshing with said second sun gear, a second ring gear meshing with said second planetary gear, said second ring gear being attached to said driven arm and under control of the iirst planetary gear, supporting means for the second planetary gear on the first ring gear, independently operable clutches for driving said sun gears independently or together, a brake for said second sun gear, means responsive to speed of the prime mover for first closr ing in the clutch of the first sun gear, means responsive to speed of the driven member for applying said last-named brake without opening the last-named clutch, means responsive to a higher speed of the driven member for releasing said last-named brake and closing the clutch of the second sun gear without opening the clutch of the first sun gear, and means for closing the second sun gear clutch without setting the last-named brake while setting the selective lock of the first ring gear.

3. In a com-pound epicyclic transmission, a first sun gear on a first driver, a planetary gear meshing therewith, a driven arm carrying said planetary gear, a ring gear meshing with said planetary gear, a reverse-locking brake associated with said ring gear, a second sun gear on a second driver, a second planetary gear meshing with said second sun gear, a second ring gear meshing with said second planetary gear, said second ring gear being attached to said driven arm and under control of the first planetary gear, supporting means for the second planetary gear on the first ring gear, means for driving said sun gears independently or together.

a brake for said second sun gear, the pivotal supports for both sets of planetary gears being Within the points of meshing of said planetary gears with said ring gears, and means in addition to said reverse-locking brake for locking the first ring gear against rotation in either direction, said additional'locking means producing reverse drive when said first-mentioned ring gear is locked and said second sun gear is driven.

4. A transmission comprising a driving element, first and second individually controlled clutches driven thereby, tlrst and second individual driving means respectively extending from said clutches and being selectively operable thereby, a driven member, an overrunnng clutch between the driving element and the first driving means', a first rotary gear cage, an automatic reverse-locking brake limiting motion of the cage to a direction with that of the driving element, a second rotary gear cage connected to the driven member, an epicyclic gear trainv connecting the driving member from the first clutch with said driven member through said second cage and adapted to act in geared conjunction with said rst cage, an epicyclic gear train connecting the driving member from the second clutch with the first cage and adapted selectively to control its movements in the direction of motion of the driven member and acting in geared conjunction with said second cage, an electric brake controlling the rotation of said second driving member and an independent mechanical brake therefor, and an interlock for locking said first cage independently of said reverse-locking brake.

5. A transmission comprising a driving element, a pair of individually controlled clutches driven thereby, first and second individual driving members controlled by said clutches respectively, a driven member, a rotary gear cage, a reverse-locking brake limiting motion of the cage to a direction with the driving element, an epicyclic gear train connecting said first driving member with said driven member and reacting against said cage, said epicyclic gearv train including a second'gear cage rotarywith the driven member, an epicyclic gear train connecting the second driving member and said second gear cage, a second brake controlling the rotation of said second driving member, control meansl responsive to the speed of the driving element for individually closing the clutch associated with the first driving member, and means responsive lto the speed of the driven element for controlling operation of said second brake and the other clutch.

6. A transmission comprising a driving element, a pair of individually controlled electric clutches driven thereby, individual driving members controlled by said clutches respectively, a driven member, a rotary gear cage, a reverselocking brake limiting motion of the cage to a direction with the driving element, a lock for said cage adapted to block its motion in any direction, an epicyclic gear train connecting one of said driving members with said driven member and reacting against said cage, said epicyclic gear train including a second gear cage rotary with the driven member, an epicyclic gear train connecting the other driving member and said second gear cage, an electric brake controlling the rotation of said second driving member, centrifugal means responsive to the speed of the driving element for individually moving the clutch associated with the first-mentioned driving member, means responsive to the speed oi' the driven 'audace element for controlling operation of said electric brake and the other clutch, and individual manual means for operating said lock.

7. A transmission comprising a driving element, a pair of individually electrically controlled clutches driven thereby, individual driving members respectively extending from said clutches and being selectively operable thereby and together, a driven member, a first rotary gear cage, an automatically operative reverse-locking brake limiting motion of the cageto a direction with that of the driving element, a second rotary gear cage connected to the driven member for equal rotation therewith, an epicyclic gear train connecting a first one oi said driving members with said driven member through said second cage and adapted to act in geared conjunction with said first cage, an epicyclic gear train connecting the other driving member and the first cage selectively to control"its--movements in the direction of motion of the driven member and acting in geared conjunction with said second cage. an electric brake controlling the rotation of said second driving member, and a lock for locking said first cage independently of said reverse-locking brake whereby said epicyclic train from said second driving member operates as a reverse train with fixed axes to turn the driven member backwards when the first driving member is declutched. x

8. A transmission comprising a driving element, rst and second individually controlled clutches driven thereby, first and second individual driving members respectively extending from said clutches and being selectively operable thereby, a driven member, a first rotary gear cage, an automatic reverse-locking brake limiting motion of the cage to a direction with that of the driving element, a second rotary gear cage connected to the driven member, an epicyclic gear train connecting the driving member from the first clutch with said driven member through said second cage and adapted to act in geared conjunction wtih said first cage, an epicyclic gear train connecting the driving member from the second clutch with the first cage and adapted selectively to control its movements in the direction of motion of the driven member and acting in geared conjunction with said second cage, a

brake controlling the rotation of said second driving member, a lock for locking said first cage independently of said reverse-locking brake whereby said epicyclic train from said second driving member operates as a reverse train with fixed axes to turn the driven member backwards when the 'rst driving member is declutched, means for automatically first holdingr closed said first clutch for low-gear operation, then setting the brake for said second driving member before opening the first clutch thus providing for sec ond-gear operation, substantially simultaneously releasing the last-named brake while holding closed both clutches for high-gear operation, and means simultaneously releasing the last-named brake and holding closed the second clutch while setting said lock for reverse-gear operation.

9. A transmission comprising a driving element, first and second individually electrically controlled clutches driven thereby, first and second individual driving members respectively extending from said clutches and being selectively operable thereby, a driven member, an overrunning clutch between the driving element and the driving member extending from the first clutch, a first rotary gear cage, an automatic reverse- 18 locking brake limiting motion 'of the cage to a direction with that of the driving element, a second rotary gear cage connected to the driven member, an epicyclic gear train connecting the first driving member from the first clutch with said driven member through said second cage and adapted to act in geared conjunction with said first cage, an epicyclic gear train connecting the second drivingA member from the second. clutch with the first cage and adapted selectively to control its movements in the direction of motion of the driven member and acting in geared conjunction with said second cage, an electrically controlled eddy-current brake controlling the rotation of said second driving member, a lack for locking said first cage independently of said reverse-locking brake whereby said epicyclic train from said second driving member operates as o, reverse train with fixed axes to turn the driven member backwards when the iirst driving means is declutched, member for automatically first holding closed said first clutch for low-gear operation, then setting the electric brake before opening the first clutch thus providing for second-gear operation, substantially simultaneously releasing the electric brake while holding `closed both clutches for high-gear operation, means for simultaneously releasing the electric brake and'holding closed the second clutch while setting said lock for reverse-gear operation, and a non-electric brake element for said electric brake for use in connection with said second drivingr member to transfer torque from the( driven member to the driving element through said overrimning clutch when the clutches and brake are released for lack of electric control current.

10. A transmission comprising a driving member, individually operable clutches driven thereby, a low-speed driver connected to one clutch, a second-speed driver connected to the other clutch, sun gears on said low and second-speed drivers, a driven member, a rotary gear cage, a reverse locking brake limiting motion of the gear cage in the direction of motion of said driving member, a lock for said gear cage adapted selectively to prevent any rotation thereof, a second gear cage attached to said driven member and carrying epicyclic 'gears meshing with the sun gear on the low-speed driving member and with the first-mentioned gear cage, epicyclic gears carried on said first-mentioned gear cage meshing with the sun gear on the second driving member and with the second gear cage, electromagnetic means for closing in the first clutch, a variable resisting circuit lfor said electromagnetic means responsive to speed change of the driving member for gradually closing in the clutch with speed increase. a control circuit for the electric brake. switch means therein responsive to a, predetermined speed of the driven member for energizing said electric brake, electromagnetic means for operating the other clutch, a control circuit for said last-named means, means in said lastnamed control circuit responsive to speed of the driven member for closing the circuit to energize said second clutch, and means connecting the control circuit for the second clutch and the control circuit for said electric brake whereby the latter circuit is opened automatically whenever the former is closed.

11. A transmission comprising a driving member itself driven by a prime mover of the internal combustion type having a vacuum manifold, individually operable clutches driven thereby, a

19 1 low-speed driver connected to one clutch, a second-speed driver connected to the other clutch, sun gears on said low and second-speed drivers, a driven member, a rotary gear cage, a reverse locking brake limiting motion of' the gear cage in the direction of motion o! said driving member, an interlock for said gear cage adapted selectively to prevent any rotation thereof, a. second gear cage attached to said driven member and carrying epicyclic gears meshing with the sun gear on the low-speed driving member and with the first-mentioned gear cage, epicyclic gears carried on said first-mentioned gear cage meshing with the sun gear on the second-speed driving member and with the second gear cage, electromagnetic means for closing in the iirst clutch, a variable resisting circuit for said electromagnetic means responsive to speed change of the driving member for gradually closing in the clutch with speed increase, a control circuit for the electric brake, switch means therein responsive to a predetermined speed of the driven member for energizing said electric brake, electromagnetic means for operating the other clutch, a control crcuit for said last named means, means in said last-named control circuit responsive to speed of the driven member for closing the circuit to energize said second clutch, means connecting the control circuit for the second v clutch and the control circuit for said electric brake whereby the latter circuit is opened Whenever the former is closed, and means responsive to manifold vacuum of said prime mover for delaying closure of the circuit for operating the electric brake until a predetermined manifold vacuum is attained.

12. A transmission comprising a driving member itself driven by a prime mover of the internal combustion type having a vacuum manifold individually operable clutches driven thereby, a lowspeed driver connected to one clutch, a secondspeed driver connected to the other clutch, sun gears on said low and second-speed drivers, a driven member, a rotary gear cage, a reverse locking brake limiting motion of the gear cage in the direction of motion of said driving member, an interlock for said gear cage adapted selectively to prevent any rotation thereof, a second gear cage attached to said driven member and carrying epicyclic gears meshing with the sun gear on the low-speed driving member and with the rstmentioned gear cage, epicyclic gears carried on said first-mentioned gear cage meshing with the sun gear on the second-speed driving member and with the second gear cage, variable electromagnetic means for closing in the rst clutch, a variable resisting circuit for said electromagnetic means responsive to speed change of the driving member for gradually closing in the clutch with speed increase, a Icontrol circuit for the electric brake, switch means therein responsive to a predetermined speed of the driven member for energizing said electric brake, electromagnetic means for operating the other clutch, a control circuit for said last-named means, means in said lastnamed control circuit responsive to speed of the driven member for closing the circuit to energize said second clutch, means connecting the control circuit for the second clutch and the control circuit for said electric brake whereby the latter circuit is opened Whenever the former is closed, and means responsive to a predetermined manifold vacuum for delaying closure of the circuit for the electric brake above a predetermined manifold pressure, said last-named means also being operative upon the control circuit for said second clutch likewise to delay its closure.

13. A transmission comprising a driving member itself driven by a, prime mover having a vacuum manifold and a throttle, individually operable clutches driven thereby, a low-speed driver connected to one clutch, a second-speed driver connected to the other clutch, sun gears on said low and second-speed drivers, a driven member, a. rotary gear cage, a reverse-locking brake limiting motion of the gear cage in the direction of motion of said driving member, an interlock for said gear cage adapted selectively to prevent any rotation thereof, a second gea-r cage attached to said driven member and carrying epicyclic gears meshing with the sun gear on the low-speed driving member and with the first-mentioned gear cage, epicyclic gears carried on said first-mentioned gear cage meshing with the sun gear on the second-speed driving member and with the secondl gear cage, variable electromagnetic means for closing in the iirst clutch, a variable resisting circuit for said electromagnetic means responsive to speed of the driving member for gradually closing in the clutch with speed increase to produce 10W speed, a control circuit for the electric brake, switch means therein responsive to a predetermined spe-ed of the driven member for energizing said electric brake to produce second speed, electromagnetic means for operating the other clutch, a control circuit for said last-named means, means in said last-named control circuit responsive to speed of the driven member for closing the circuit to energize said second clutch to produce high speed, means connecting the control circuit for the second clutch and the control circuit for said electric brake whereby the latter circuit is opened Whenever the former is closed, means responsive to manifold vacuum of the prime mover for delaying closure of the circuit for the electric brake until a predetermined manifold vacuum is reached, said last-named means also being operative upon the control circuit for said second clutch, and means responsive to a. predetermined throttle opening of said prime mover for breaking said circuit of the second clutch.

14. A transmission for an internal combustion engine which has a vacuum manifold, comprising a main driving means driven from said engine, a pair of individually operable clutches. plural driving members extending from the clutches, a driven member, compound epicyclic gea-r means connecting said plural driving members with said driven member, an electric brake associated with one driving member, the arrangement being such that closure of a first one of said clutches institutes low gear, while energization of said electric brake institutes second gear, and deenergization of said brake and closure of both clutches institutes high gear, means responsive to prime mover speed for closing in the low-speed clutch, means responsive to the speed of the driven member for energizing the brake to institute second-speed operation, said last-named means being also responsive to reduced manifold pressure of said prime mover to delay institution of second-speed operation, and means responsive to the speed of the driven member for instituting high-speed operation, said last-named means also being subject to delay determined by manifold pressure in the prime mover.

15. A transmission comprising a main driving means driven from an internal combustion enmain driving means, driving members extending from the clutches, a driven member, compound epicyclic gear means connecting said driving members with said driven'member, an electric brake connected with one of said driving members, the arrangement being such that closure of a flrst one of said clutches institutes low gear, while energization of said electric brake institutes second gear during the time that said first clutch remains closed, and deenergization of said brake and closure of both clutches institutes high gear, means responsive to prime mover speed for closing in the low-speed clutch to institute low speed, means responsive to the 'speed of the driven member for energizing the brake to institute second-speed operation, said last-named means being also responsive to reduced manifold pressure of said prime mover to delay institution of second-speed operation, means responsive to the driven member for instituting high-speed operation, saidlast-named means also being subject to delay determined by manifold pressure in the prime mover, means for deenergizing said electric brake when both of said clutches are closed,

' and means for maintaining the second-speed or tending from the clutches, a driven member,

compound epicyclic gear means connecting said driving members with said driven member, an electric brake connected with one of said driving members, the arrangement being such that closure of a first one of said clutches institutes low gear, while energization of said electric brake institutes second gear, and deenergization of said brake and closure of both clutches institutes high gear, means responsive to prime mover speed for closing in the low-speed clutch to institute low speed, means responsive to the speed of the driven member for energizing the brake to institute second-speed operation, said lastnamed means being also responsive to reduced manifold pressure of said prime mover to delay institution of second-speed operation, means responsive to speed of the driven member for instituting high-speed operation, said last-named means also being subject to delay determined by manifold pressure in the prime mover, means for deenergizing said electric brake when both of said clutches are closed, means for maintaining second-speed andfhigh-speed operations respectively when once instituted independentlyl of said manifold pressure, means responsive to a predetermined position of said throttle of said prime mover for opening the circuit to said highspeed clutch, and means responsive to opening of the last-named circuit whereby said electric brake automatically again becomes energized to institute second-speed operation.

17. An electrically controlled transmission adapted to be driven by a prime mover, comprisnorm ally closed switch;

met clutch when closed 'to modify the ratio or said gear train to institute second-speed operation, a control coil for said electric brake, a. second clutch adapted when actuated to close in conjunction with said first clutch when closed furtherto couple the elements of said gear train to institute direct high-speed operation of said driven member, a control coil for said second clutch; a first circuit including said first clutch control coil and a rheostat responsive to prime mover speed adapted variably to actuate said first clutch; a second circuit adapted to actuate said electric brake including said brake coil, a first switch responsive to motion of said driven member to close at a predetermined speed, and a second normally closed switch; and a third circuit adapted to actuate said second clutch including said second clutchcoil, Aa vthird switch responsive to speed of said driven member, and a magnetic coil operating said second switch, said second switch being responsive to energization of said magnetic coil to open said second circuit when said third circuit is completed.

18. An electrically controlled transmission adapted to be driven by a prime mover having n. vacuum manifold. comprising a first clutch, an electric control coil therefor, a driven member, a gear train adapted to be driven by said prime mover through said first clutch to institute lowspeed operation of said driven member when said clutch coil is energized to close the clutch,

an electric brake adapted when actuated in conjunction with said first clutch to modify the ratio of said gear train to institute secondspeed operation of said driven member, an electric brake control coil for said brake, a second clutch adaptedl when actuatedto close in conjunction with said first clutch when closed further to modify the ratio of said gear train to institute high-speed operation of said driven member, a control coil for said second clutch; a first circuit including said first clutch coil and a rheostat responsive to prime mover speed adapted variably to actuate said first clutch; a second circuit adapted to energize said electric brake includingr said brake coil, a first switch responsive to motion of said driven member to close at a predetermined speed, a second switch responsive to manifold vacuum to delay energization of the brake coil until a predetermined manifold vacuum is reached, a magnetic holding switch across said last-named switch, and a third and a third circuit adapted to actuate said second clutch including said second clutch coil, a fourth switch responsive to speed of the driven member for closing the circuit. a fifth switch responsive to manifold vacuum to close when said vacuum reaches a predetermined value, a holding coil for said last-named switch, and a magnetic coil responsive to energization of said third circuit to open said' third switch to deenergize said second circuit.

19. An electrically controlled transmission adapted to be driven by a prime mover having a throttle, comprising a first clutch, an electric clutch control coil therefor, a driven member, a gear train adapted to be driven by said prime mover through said first clutch to institute lowspeed operation of said driven member when said clutch coil is energized to close the clutch, an electric brake adapted when actuated in conjunction with said first clutch to modify the ratio of said gear train to `institute second-speed operation, a coil for said electric brake, a second clutch adapted when actuated to close in conjunction with said first clutch when closed further to modify the ratio of said gear train to institute high-speed operation of said driven member, a control coil for said second clutch; a first circuit including said rst clutch coil and a rheostat responsive to prime mover speed adapted variably to actuate said first clutch; a second circuit vadapted to actuate said electric brake including said brake coil, a first switch r'esponsive to motion of saidudriven member to close at a predetermined speed; and a second normally closed switch; a third circuit adapted to actuate said second clutch including said second clutch coil, a third switch responsive to speed of said driven member and a magnetic coil operative upon said second switch, said second switch being responsive to energization of said magnetic coil to open said second circuit when said third circuit is'completed, and a Ithrottle-operated switch in said third circuit adapted at a predetermined throttle opening to deenergize the third circuit and reenergize said second circuit to institute second-speed operation.`

20. An electrically controlled transmission adapted to be driven by a prime mover, comprising a first clutch, an electric clutch control coil therefor, a driven member, a gear train adapted to be driven by said prime mover through said first clutch to institute low-speed operation of said driven member when said clutch coil is energized to close the clutch, an electric brake adapted when actuated in conjunction with said first clutch to modify the ratio of said gear train to institute second-speed operation, a control coil for said electric brake, a Second clutch adapted when actuated to close in commotion with said first clutch when closed further to modify the ratio of said gear train to institute high-speed operation of said driven member, a control coil for said second clutch; a first circuit including said first clutch coil and a rheostat responsive to prime mover speed adapted variably to actuate said iirst clutch; a second circuit adapted to actuate said electric brake including said brake coil, a first switch responsive to motion of said driven member to close at a predetermined speed, and a second normally closed switch; a third circuit adapted to actuate said second clutch including said second clutch coil, a third switch responsive to speed of said driven member and a magnetic coil operative upon said second switch, said second switch being responsive to energization of said magnetic coil to deactuate said electric brake when said third circuit is completed, and a gang of manually operated switches each in one of said circuits, manual operation being adapted substantially simultaneously to open the switches in all of said circuits.

21. An electrically controlled transmission adapted to be driven by a prime mover, comprising a first clutch, an electric cluch control coil therefor, a driven member, a gear train adapted rto be driven by said prime mover through said first cl-utch to institute low-speed operation of said driven member when said clutch coil is energized to close the clutch, an electric brake adapted when actuated in conjunction with said first clutch to modify the ratio of said gear train to institute second-speed operation, a control coil for said electric brake, a second clutch adapted when actuated to close in conjunction with said first clutch when closed further to modify the ratio of said gear train to institute high-speed operation of said driven member, a control coil for said second clutch; a first circuit including said first clutch coil and a rheostat responsive to prime mover speed adapted variably to actuate said first clutch, a second circuit adapted to actuate said electric brake including said/brake coil, a rst switch responsive to motion of said driven member to close at a predetermined speed, and a second normally closed switch, a third circuit adapted to actuate saidsecond clutch including said second clutch coil, a third switch responsive to speed of said driven member and a magnetic coil operative upon said second switch, said second switch being responsive to energization of said magneitc coil to deactuate said electric brake when said third circuit is completed; and a fourth circuit including said rheostat and said second clutch coil adapted to actuate only said second clutch to institute reverse-speed operation of said driven member.

22. A transmission comprising a main driving unit, a pair of rst and second individually operable clutches adapted to be selectively driven by said driving unit, a first driving member extending from said first clutch and carrying a first s-un gear, a second driving member extending from said second clutch and carrying a second sun gear and an electrically actuated brake, a first planetary gear meshed with said first sun gear, a driven rotary arm carrying said rst planetary gear, a rst ring gear meshed with said rst planetary gear, a one-way locking brakeassociated with said ring gear, a second planetary gear meshed with said second sun gear, a second ringv gear meshed with said second planetary gear, said second ring gear being attached to said driven rotary arm and being coordinated with the planetary action of said first planetary gear, and a cage supporting the second planetary gear on the first ring gear whereby said iirst ring gear is c0- ordinated with the planetary action of said second planetary gear, a rst electric coil associated with said first clutch responsive to the speed of said driving unit to actuate said first clutch, a second electric coil associated with said second clutch responsive to the speed of said driven member to actuate said second clutch, and an electric circuit including said electrically actuated brake responsive to speed of said driven member to actuate said brake.

23. A transmission for an internal combustion engine, comprisinga main driving means driven from said engine, a pair of individually operable clutches, plural driving members extending from the clutches, a driven member, compound epicyclic gear means connecting said plural driving members with said driven member, an electric brake associated with one driving member, the arrangement being such lthat closure of a first one of said clutches institutes low-gear operation, while energization of said electric brake without opening the rst clutch institutes second-gear operation, and deenergization of said brake and closure of both clutches institutes high-gear operation, a rst electrical circuit responsive to prime mover speed for closing the low-gear clutch, a second electrical circuit responsive to the speed of the driven member for energizing the brake to institute second-gear operation, and a third electrical circuit responsive to the speed of the driven member for instituting high-gear operation.

24. A transmission for .an internal combustion engine, comprising a main driving means driven from said engine, a pair of individually operable clutches, plural driving members Y extending 

